The other day, my ignition cut off completely during a several hour drive
on a pretty warm day. I've been having this intermittent missing after a
few hour drive, but I haven't tracked it down. The point gap was .006
with a worn rubbing pad, so I got a new one and a new condenser.
Now I'm trying to get the ignition sorted out. For something so simple,
it sure has me boggled, but when it comes to electricity, I'm pretty much
an idiot anyway. (I remember when I was little sticking my finger in
Grandma's empty desk lamp light socket to see which way to push the
button to turn it on. Worse part is, I remember doing this on two
separate occasions!!)
So, I've got the new points in and adjusted to exactly .015 gap. I've got
the new condenser in, but I've since checked the old one, and it was OK,
too (.2 mF.) I've replaced the questionable internal wiring, cleaned
everything completely, and put it all back together. I've gone through
the 9-step low tension wiring check, and I've checked the coil for
internal grounding and correct resistance (~3.5 Ohm.) I get spark at the
coil (jumps about 3/8", but I don't know how bright or "snappy" it should
be.) Still no joy.
All that's left in the entire circuit is the cap, rotor, plug wires, coil
wire, and plugs. I am not getting any spark at all at any plug! I checked
for continuity though the cap's center electrode to the end of the coil
wire, so that's good.
So I just pulled each spark plug wire and checked for continuity.
Nothin'. Nada. Zip. All four wire show no continuity from the bare end to
the snap-on boot at the plug end. Further, I've poked the digital VOM's
probe though the wire sheath at the plug end, and checked back to the
bare end, and I get continuity, and a reading of .3 Ohm on my lowest
(highest) 200 Ohm scale. I get no reading or continuity from the wire
immediately behind the snap-on plug boot through the boot itself (I'm
talking about the molded phenolic cap/boot that snaps over the spark
plug.) Is there a resistor in there? Is it so high a resistance that it
would show as an open circuit with no continuity on a digital VOM? If
not, how in the world could I have failed all four at once? Since I get
spark at the coil, and nothing at the plug, it has to be either in the
plug wires, or not a strong enough spark to jump the gap between the
dizzy cap and the rotor.
Help, I'm confused, electrically challenged, and it is only eight days
until the Mid-Ohio vintage races!
Steve
Steve Morris Avon, Ohio
1958 MGA 1500 Red/Black
NAMGAR #5987 BuckAyes Ohio Chapter
LoCo Brits <mailto: MGA1500@mac.com>
http://www.en.com/users/smorris/mga/
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